This is a set of two books. The "Ooiwa's First English Grammar" book has been used about 80% of the way through. I made marks with a mechanical pencil, but I erased them. There may be some overlooked marks or traces left. On the first few pages, there are checks made with a ballpoint pen as shown in the photos. Also, please understand that the cover shows signs of use. For the "English Long Passage Level-Based Problem Collection," there are some markings made with a mechanical pencil on the first page. I erased them, but traces remain. Other than that, it has not been touched and is clean.